We sell our products to wholesale distributors, specialty pharmacies, specialty distributors, and chain drug stores that generally sell products to retail pharmacies, hospitals, and other institutional customers.

Customers with product revenue equal to or greater than 10% of our total revenue for the periods indicated were as follows:

	2021	2020	2019
Customer A	11%	21%	37%
Customer B	15%	16%	11%
Customer C	17%	28%	13%
Customer E	12%	*	*
Customer F	*	*	12%
* Less than 10% of total product revenue

Customers that accounted for 10% or greater of our accounts receivable as of the periods indicated were as follows:

	As of December 31,
	2021	2020
Customer A	*	17%
Customer B	21%	19%
Customer C	35%	25%
Customer D	11%	11%
* Balance was less than 10% of accounts receivable, gross

We rely on third parties for the manufacture and supply of our products, as well as third-party logistics providers. In instances where these parties fail to perform their obligations, we may be unable to find alternatives suppliers or satisfactorily deliver our products to our customers on time, if at all.

Vendors with product purchases equal to or greater than 10% of our total purchases for the periods indicated were as follows:

	2021	2020	2019
Catalent	33%	30%	24%
Vendor A	36%	25%	*
Vendor B	27%	36%	27%
Vendor I	*	*	35%
* Less than 10% of total product purchases

Vendors that accounted for 10% or greater of our accounts payable as of the periods indicated were as follows:

	As of December 31,
	2021	2020
Vendor E	19%	17%
Vendor F	20%	16%
Vendor G	*	10%
* Balance was less than 10% of total accounts payable